【資料名稱】：美國建模競賽直放站的問題

【資料作者】：張訓(xùn)力 朱馬峰 王亞星

【資料日期】：2010

【資料語言】：英文

【資料格式】：PDF

【資料目錄和簡介】：


Abstract
With the development of communication technology Relay communication attract much more attention. Firstly, this article with professional knowledge of communication, describes the working principle of relay stations and CTCSS used to reduce interference between repeaters. The main factors which limit the number of repeater stations in a region are: the number of users, the number of frequencies, PL number, sizes of the area. In the process of solving the first problem, in order to obtain the minimum number of repeaters to meet the requirements, firstly, we use a certain number of repeaters to cover the entire area, then keep adding repeaters, finally we get the minimum number of repeaters 197 to meet constraints. As for the second problem, taking into account the complexity of factors of using the network to meet the needs of 10,000 users, we use fast simulated annealing algorithm to construct a new mathematical model, making the problem of greatly simplified. Eventually by programming the calculation, we get the minimum required number of repeater stations is 1500.In the discussion of the third problem, firstly, according to the propagation characteristics of microwave. We analyzed the line of sight transmission defects in the mountains, the complexity of the mountains lead to the process of signal transmission of severe scattering, reflection and diffraction phenomena, which greatly reduce the effectiveness of communication transmission. In this regard, this paper using the two-tier network of networking to overcome this defect of the line of sight transmission in the mountains. In the end of the article we analysis the advantages and disadvantages of the model and propose an improved approach to optimize the model.